HP-UX Directory Server 8.1 administrator guide

8 Managing replication
Replication is the mechanism by which directory data is automatically copied from one HP-UX
Directory Server instance to another; it is an important mechanism for extending the directory
service beyond a single server configuration. This chapter describes the tasks to be performed
on the master and consumer servers to set up single-master replication, multi-master replication,
and cascading replication.
Topics include:
• “Replication overview” (page 319)
• “Replication scenarios” (page 322)
• “Creating the supplier bind DN entry” (page 325)
• “Configuring single-master replication” (page 327)
• “Configuring multi-master replication” (page 336)
• “Configuring cascading replication” (page 350)
• “Configuring replication from the command line” (page 364)
• “Making a replica updatable” (page 372)
• “Deleting the changelog” (page 372)
• “Initializing consumers” (page 373)
• “Forcing replication updates” (page 377)
• “Replicating account lockout attributes” (page 379)
• “Replication over SSL” (page 380)
• “Replicating o=NetscapeRoot for Administration Server failover” (page 380)
• “Replication with earlier releases” (page 381)
• “Using the Retro changelog plug-in” (page 382)
• “Monitoring replication status” (page 384)
• “Solving common replication conflicts” (page 386)
• “Troubleshooting replication-related problems” (page 389)
8.1 Replication overview
Replication is the mechanism by which directory data is automatically copied from one Directory
Server to another. Updates of any kind (entry additions, modifications, or even deletions) are
automatically mirrored to other Directory Servers using replication. This section contains
information on the following replication concepts:
• “What directory units are replicated”
• “Read-write and read-only replicas”
• “Suppliers and consumers”
• “Changelog”
• “Replication identity”
• “Replication agreement”
• “Compatibility with earlier versions of directory server”
8.1.1 What directory units are replicated
The smallest unit of the directory that can be replicated is a database. This means that one can
replicate an entire database but not a subtree within a database. Therefore, when creating the
directory tree, consider any replication plans as part of determining how to distribute information.
Replication also requires that one database correspond to one suffix. This means that a suffix (or
namespace) that is distributed over two or more databases using custom distribution logic cannot
be replicated. For more information on this topic, see “Creating and maintaining databases”.
8.1 Replication overview 319